Can we have independent staves in Dorico regarding time signatures, key signatures? This is for polyrhythm and politonality
Is it possible in a score for piano to assign a different piano to each stave-hand)? This is to have different dynamics for each hand.
For example.
yes, it is all possible already 
No, it’s not. If you look at the example Xinver wants a 7/8 bar in one hand that coincides with a 5/4 bar in the other hand - effectively 7 (quavers/eighths) against 10 (quavers/eighths). Simple polymeter - where the underlying pulse is the same (quaver = quaver or eighth = eighth) is absolutely possible. Advanced polymeter, where for example 7 quavers/eighths = 10 quavers/eighths is not possible yet.
Thanks!
I imported an xml file with that kind of polymeter, and Dorico took it (with errors).
But how can it be done in Dorico? The question is how to separate staves to have different parameters.
For just simple polymeter click where you want the time signature (meter), type Shift-M, type in what you want and then it’s Alt-Enter. Enter will put it on every staff, Alt-Enter will only put it on one staff (though you can select the time signature and alt-click it to other staves to quickly copy and paste).
It is possible with a bit of faking, if the barlines coincide as in this example.
To get the time signature on the bottom staff, create a 7/8 signature with a pickup bar ten 8th-notes long (yes, pickup bars can be longer than the time signature!) Then change to a 5/4 time signature in the second bar and hide it.
To enter the notes on the bottom staff, create 7:10 tuplets and hide them.
Is there a way to have Dorico show a 2/4 staff that plays in the time of a 6/8 such that the barlines line up (showing quarter notes in the piano but implied dotted quarters to line up with the violin – quarter = dotted quarter). Thanks for anyone’s help!
Yes, by using Rob’s method described above.
At the first bar in the bottom staff, open the popover, type 2/4 ,3 and press ALT+enter.
In the second bar, create a 6/8 signature and hide it through the properties panel. You’ll have to use tuplets to get the rhythms aligned correctly so it’s a bit quirky, but it looks good, and will playback correctly.
I seem to remember that this was the original plan (each VOICE having its own “endpoint” [midi ch/xmap]) but currently, a piano system is limited to a single channel, and all dynamic markings, regardless of placement, unfortunately affect all voices…
Thanks andgle and Rob!
